1 /* 2 * PowerPC version 3 * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) 4 * 5 * Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au) 6 * and Cort Dougan (PReP) (cort@cs.nmt.edu) 7 * Copyright (C) 1996 Paul Mackerras 8 * Amiga/APUS changes by Jesper Skov (jskov@cygnus.co.uk). 9 * PPC44x/36-bit changes by Matt Porter (mporter@mvista.com) 10 * 11 * Derived from "arch/i386/mm/init.c" 12 * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds 13 * 14 * This program is free software; you can redistribute it and/or 15 * modify it under the terms of the GNU General Public License 16 * as published by the Free Software Foundation; either version 17 * 2 of the License, or (at your option) any later version. 18 * 19 */ 20 21 #include <linux/config.h> 22 #include <linux/module.h> 23 #include <linux/sched.h> 24 #include <linux/kernel.h> 25 #include <linux/errno.h> 26 #include <linux/string.h> 27 #include <linux/types.h> 28 #include <linux/mm.h> 29 #include <linux/stddef.h> 30 #include <linux/init.h> 31 #include <linux/bootmem.h> 32 #include <linux/highmem.h> 33 #include <linux/initrd.h> 34 #include <linux/pagemap.h> 35 36 #include <asm/pgalloc.h> 37 #include <asm/prom.h> 38 #include <asm/io.h> 39 #include <asm/mmu_context.h> 40 #include <asm/pgtable.h> 41 #include <asm/mmu.h> 42 #include <asm/smp.h> 43 #include <asm/machdep.h> 44 #include <asm/btext.h> 45 #include <asm/tlb.h> 46 #include <asm/prom.h> 47 #include <asm/lmb.h> 48 #include <asm/sections.h> 49 #include <asm/vdso.h> 50 51 #include "mmu_decl.h" 52 53 #ifndef CPU_FTR_COHERENT_ICACHE 54 #define CPU_FTR_COHERENT_ICACHE 0 /* XXX for now */ 55 #define CPU_FTR_NOEXECUTE 0 56 #endif 57 58 int init_bootmem_done; 59 int mem_init_done; 60 unsigned long memory_limit; 61 62 extern void hash_preload(struct mm_struct *mm, unsigned long ea, 63 unsigned long access, unsigned long trap); 64 65 /* 66 * This is called by /dev/mem to know if a given address has to 67 * be mapped non-cacheable or not 68 */ 69 int page_is_ram(unsigned long pfn) 70 { 71 unsigned long paddr = (pfn << PAGE_SHIFT); 72 73 #ifndef CONFIG_PPC64 /* XXX for now */ 74 return paddr < __pa(high_memory); 75 #else 76 int i; 77 for (i=0; i < lmb.memory.cnt; i++) { 78 unsigned long base; 79 80 base = lmb.memory.region[i].base; 81 82 if ((paddr >= base) && 83 (paddr < (base + lmb.memory.region[i].size))) { 84 return 1; 85 } 86 } 87 88 return 0; 89 #endif 90 } 91 EXPORT_SYMBOL(page_is_ram); 92 93 pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn, 94 unsigned long size, pgprot_t vma_prot) 95 { 96 if (ppc_md.phys_mem_access_prot) 97 return ppc_md.phys_mem_access_prot(file, pfn, size, vma_prot); 98 99 if (!page_is_ram(pfn)) 100 vma_prot = __pgprot(pgprot_val(vma_prot) 101 | _PAGE_GUARDED | _PAGE_NO_CACHE); 102 return vma_prot; 103 } 104 EXPORT_SYMBOL(phys_mem_access_prot); 105 106 #ifdef CONFIG_MEMORY_HOTPLUG 107 108 void online_page(struct page *page) 109 { 110 ClearPageReserved(page); 111 init_page_count(page); 112 __free_page(page); 113 totalram_pages++; 114 num_physpages++; 115 } 116 117 int __devinit add_memory(u64 start, u64 size) 118 { 119 struct pglist_data *pgdata; 120 struct zone *zone; 121 int nid; 122 unsigned long start_pfn = start >> PAGE_SHIFT; 123 unsigned long nr_pages = size >> PAGE_SHIFT; 124 125 nid = hot_add_scn_to_nid(start); 126 pgdata = NODE_DATA(nid); 127 128 start = (unsigned long)__va(start); 129 create_section_mapping(start, start + size); 130 131 /* this should work for most non-highmem platforms */ 132 zone = pgdata->node_zones; 133 134 return __add_pages(zone, start_pfn, nr_pages); 135 136 return 0; 137 } 138 139 /* 140 * First pass at this code will check to determine if the remove 141 * request is within the RMO. Do not allow removal within the RMO. 142 */ 143 int __devinit remove_memory(u64 start, u64 size) 144 { 145 struct zone *zone; 146 unsigned long start_pfn, end_pfn, nr_pages; 147 148 start_pfn = start >> PAGE_SHIFT; 149 nr_pages = size >> PAGE_SHIFT; 150 end_pfn = start_pfn + nr_pages; 151 152 printk("%s(): Attempting to remove memoy in range " 153 "%lx to %lx\n", __func__, start, start+size); 154 /* 155 * check for range within RMO 156 */ 157 zone = page_zone(pfn_to_page(start_pfn)); 158 159 printk("%s(): memory will be removed from " 160 "the %s zone\n", __func__, zone->name); 161 162 /* 163 * not handling removing memory ranges that 164 * overlap multiple zones yet 165 */ 166 if (end_pfn > (zone->zone_start_pfn + zone->spanned_pages)) 167 goto overlap; 168 169 /* make sure it is NOT in RMO */ 170 if ((start < lmb.rmo_size) || ((start+size) < lmb.rmo_size)) { 171 printk("%s(): range to be removed must NOT be in RMO!\n", 172 __func__); 173 goto in_rmo; 174 } 175 176 return __remove_pages(zone, start_pfn, nr_pages); 177 178 overlap: 179 printk("%s(): memory range to be removed overlaps " 180 "multiple zones!!!\n", __func__); 181 in_rmo: 182 return -1; 183 } 184 #endif /* CONFIG_MEMORY_HOTPLUG */ 185 186 void show_mem(void) 187 { 188 unsigned long total = 0, reserved = 0; 189 unsigned long shared = 0, cached = 0; 190 unsigned long highmem = 0; 191 struct page *page; 192 pg_data_t *pgdat; 193 unsigned long i; 194 195 printk("Mem-info:\n"); 196 show_free_areas(); 197 printk("Free swap: %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10)); 198 for_each_online_pgdat(pgdat) { 199 unsigned long flags; 200 pgdat_resize_lock(pgdat, &flags); 201 for (i = 0; i < pgdat->node_spanned_pages; i++) { 202 if (!pfn_valid(pgdat->node_start_pfn + i)) 203 continue; 204 page = pgdat_page_nr(pgdat, i); 205 total++; 206 if (PageHighMem(page)) 207 highmem++; 208 if (PageReserved(page)) 209 reserved++; 210 else if (PageSwapCache(page)) 211 cached++; 212 else if (page_count(page)) 213 shared += page_count(page) - 1; 214 } 215 pgdat_resize_unlock(pgdat, &flags); 216 } 217 printk("%ld pages of RAM\n", total); 218 #ifdef CONFIG_HIGHMEM 219 printk("%ld pages of HIGHMEM\n", highmem); 220 #endif 221 printk("%ld reserved pages\n", reserved); 222 printk("%ld pages shared\n", shared); 223 printk("%ld pages swap cached\n", cached); 224 } 225 226 /* 227 * Initialize the bootmem system and give it all the memory we 228 * have available. If we are using highmem, we only put the 229 * lowmem into the bootmem system. 230 */ 231 #ifndef CONFIG_NEED_MULTIPLE_NODES 232 void __init do_init_bootmem(void) 233 { 234 unsigned long i; 235 unsigned long start, bootmap_pages; 236 unsigned long total_pages; 237 int boot_mapsize; 238 239 max_pfn = total_pages = lmb_end_of_DRAM() >> PAGE_SHIFT; 240 #ifdef CONFIG_HIGHMEM 241 total_pages = total_lowmem >> PAGE_SHIFT; 242 #endif 243 244 /* 245 * Find an area to use for the bootmem bitmap. Calculate the size of 246 * bitmap required as (Total Memory) / PAGE_SIZE / BITS_PER_BYTE. 247 * Add 1 additional page in case the address isn't page-aligned. 248 */ 249 bootmap_pages = bootmem_bootmap_pages(total_pages); 250 251 start = lmb_alloc(bootmap_pages << PAGE_SHIFT, PAGE_SIZE); 252 253 boot_mapsize = init_bootmem(start >> PAGE_SHIFT, total_pages); 254 255 /* Add all physical memory to the bootmem map, mark each area 256 * present. 257 */ 258 for (i = 0; i < lmb.memory.cnt; i++) { 259 unsigned long base = lmb.memory.region[i].base; 260 unsigned long size = lmb_size_bytes(&lmb.memory, i); 261 #ifdef CONFIG_HIGHMEM 262 if (base >= total_lowmem) 263 continue; 264 if (base + size > total_lowmem) 265 size = total_lowmem - base; 266 #endif 267 free_bootmem(base, size); 268 } 269 270 /* reserve the sections we're already using */ 271 for (i = 0; i < lmb.reserved.cnt; i++) 272 reserve_bootmem(lmb.reserved.region[i].base, 273 lmb_size_bytes(&lmb.reserved, i)); 274 275 /* XXX need to clip this if using highmem? */ 276 for (i = 0; i < lmb.memory.cnt; i++) 277 memory_present(0, lmb_start_pfn(&lmb.memory, i), 278 lmb_end_pfn(&lmb.memory, i)); 279 init_bootmem_done = 1; 280 } 281 282 /* 283 * paging_init() sets up the page tables - in fact we've already done this. 284 */ 285 void __init paging_init(void) 286 { 287 unsigned long zones_size[MAX_NR_ZONES]; 288 unsigned long zholes_size[MAX_NR_ZONES]; 289 unsigned long total_ram = lmb_phys_mem_size(); 290 unsigned long top_of_ram = lmb_end_of_DRAM(); 291 292 #ifdef CONFIG_HIGHMEM 293 map_page(PKMAP_BASE, 0, 0); /* XXX gross */ 294 pkmap_page_table = pte_offset_kernel(pmd_offset(pgd_offset_k 295 (PKMAP_BASE), PKMAP_BASE), PKMAP_BASE); 296 map_page(KMAP_FIX_BEGIN, 0, 0); /* XXX gross */ 297 kmap_pte = pte_offset_kernel(pmd_offset(pgd_offset_k 298 (KMAP_FIX_BEGIN), KMAP_FIX_BEGIN), KMAP_FIX_BEGIN); 299 kmap_prot = PAGE_KERNEL; 300 #endif /* CONFIG_HIGHMEM */ 301 302 printk(KERN_INFO "Top of RAM: 0x%lx, Total RAM: 0x%lx\n", 303 top_of_ram, total_ram); 304 printk(KERN_INFO "Memory hole size: %ldMB\n", 305 (top_of_ram - total_ram) >> 20); 306 /* 307 * All pages are DMA-able so we put them all in the DMA zone. 308 */ 309 memset(zones_size, 0, sizeof(zones_size)); 310 memset(zholes_size, 0, sizeof(zholes_size)); 311 312 zones_size[ZONE_DMA] = top_of_ram >> PAGE_SHIFT; 313 zholes_size[ZONE_DMA] = (top_of_ram - total_ram) >> PAGE_SHIFT; 314 315 #ifdef CONFIG_HIGHMEM 316 zones_size[ZONE_DMA] = total_lowmem >> PAGE_SHIFT; 317 zones_size[ZONE_HIGHMEM] = (total_memory - total_lowmem) >> PAGE_SHIFT; 318 zholes_size[ZONE_HIGHMEM] = (top_of_ram - total_ram) >> PAGE_SHIFT; 319 #else 320 zones_size[ZONE_DMA] = top_of_ram >> PAGE_SHIFT; 321 zholes_size[ZONE_DMA] = (top_of_ram - total_ram) >> PAGE_SHIFT; 322 #endif /* CONFIG_HIGHMEM */ 323 324 free_area_init_node(0, NODE_DATA(0), zones_size, 325 __pa(PAGE_OFFSET) >> PAGE_SHIFT, zholes_size); 326 } 327 #endif /* ! CONFIG_NEED_MULTIPLE_NODES */ 328 329 void __init mem_init(void) 330 { 331 #ifdef CONFIG_NEED_MULTIPLE_NODES 332 int nid; 333 #endif 334 pg_data_t *pgdat; 335 unsigned long i; 336 struct page *page; 337 unsigned long reservedpages = 0, codesize, initsize, datasize, bsssize; 338 339 num_physpages = lmb.memory.size >> PAGE_SHIFT; 340 high_memory = (void *) __va(max_low_pfn * PAGE_SIZE); 341 342 #ifdef CONFIG_NEED_MULTIPLE_NODES 343 for_each_online_node(nid) { 344 if (NODE_DATA(nid)->node_spanned_pages != 0) { 345 printk("freeing bootmem node %d\n", nid); 346 totalram_pages += 347 free_all_bootmem_node(NODE_DATA(nid)); 348 } 349 } 350 #else 351 max_mapnr = max_pfn; 352 totalram_pages += free_all_bootmem(); 353 #endif 354 for_each_online_pgdat(pgdat) { 355 for (i = 0; i < pgdat->node_spanned_pages; i++) { 356 if (!pfn_valid(pgdat->node_start_pfn + i)) 357 continue; 358 page = pgdat_page_nr(pgdat, i); 359 if (PageReserved(page)) 360 reservedpages++; 361 } 362 } 363 364 codesize = (unsigned long)&_sdata - (unsigned long)&_stext; 365 datasize = (unsigned long)&_edata - (unsigned long)&_sdata; 366 initsize = (unsigned long)&__init_end - (unsigned long)&__init_begin; 367 bsssize = (unsigned long)&__bss_stop - (unsigned long)&__bss_start; 368 369 #ifdef CONFIG_HIGHMEM 370 { 371 unsigned long pfn, highmem_mapnr; 372 373 highmem_mapnr = total_lowmem >> PAGE_SHIFT; 374 for (pfn = highmem_mapnr; pfn < max_mapnr; ++pfn) { 375 struct page *page = pfn_to_page(pfn); 376 377 ClearPageReserved(page); 378 init_page_count(page); 379 __free_page(page); 380 totalhigh_pages++; 381 } 382 totalram_pages += totalhigh_pages; 383 printk(KERN_INFO "High memory: %luk\n", 384 totalhigh_pages << (PAGE_SHIFT-10)); 385 } 386 #endif /* CONFIG_HIGHMEM */ 387 388 printk(KERN_INFO "Memory: %luk/%luk available (%luk kernel code, " 389 "%luk reserved, %luk data, %luk bss, %luk init)\n", 390 (unsigned long)nr_free_pages() << (PAGE_SHIFT-10), 391 num_physpages << (PAGE_SHIFT-10), 392 codesize >> 10, 393 reservedpages << (PAGE_SHIFT-10), 394 datasize >> 10, 395 bsssize >> 10, 396 initsize >> 10); 397 398 mem_init_done = 1; 399 400 /* Initialize the vDSO */ 401 vdso_init(); 402 } 403 404 /* 405 * This is called when a page has been modified by the kernel. 406 * It just marks the page as not i-cache clean. We do the i-cache 407 * flush later when the page is given to a user process, if necessary. 408 */ 409 void flush_dcache_page(struct page *page) 410 { 411 if (cpu_has_feature(CPU_FTR_COHERENT_ICACHE)) 412 return; 413 /* avoid an atomic op if possible */ 414 if (test_bit(PG_arch_1, &page->flags)) 415 clear_bit(PG_arch_1, &page->flags); 416 } 417 EXPORT_SYMBOL(flush_dcache_page); 418 419 void flush_dcache_icache_page(struct page *page) 420 { 421 #ifdef CONFIG_BOOKE 422 void *start = kmap_atomic(page, KM_PPC_SYNC_ICACHE); 423 __flush_dcache_icache(start); 424 kunmap_atomic(start, KM_PPC_SYNC_ICACHE); 425 #elif defined(CONFIG_8xx) || defined(CONFIG_PPC64) 426 /* On 8xx there is no need to kmap since highmem is not supported */ 427 __flush_dcache_icache(page_address(page)); 428 #else 429 __flush_dcache_icache_phys(page_to_pfn(page) << PAGE_SHIFT); 430 #endif 431 432 } 433 void clear_user_page(void *page, unsigned long vaddr, struct page *pg) 434 { 435 clear_page(page); 436 437 /* 438 * We shouldnt have to do this, but some versions of glibc 439 * require it (ld.so assumes zero filled pages are icache clean) 440 * - Anton 441 */ 442 flush_dcache_page(pg); 443 } 444 EXPORT_SYMBOL(clear_user_page); 445 446 void copy_user_page(void *vto, void *vfrom, unsigned long vaddr, 447 struct page *pg) 448 { 449 copy_page(vto, vfrom); 450 451 /* 452 * We should be able to use the following optimisation, however 453 * there are two problems. 454 * Firstly a bug in some versions of binutils meant PLT sections 455 * were not marked executable. 456 * Secondly the first word in the GOT section is blrl, used 457 * to establish the GOT address. Until recently the GOT was 458 * not marked executable. 459 * - Anton 460 */ 461 #if 0 462 if (!vma->vm_file && ((vma->vm_flags & VM_EXEC) == 0)) 463 return; 464 #endif 465 466 flush_dcache_page(pg); 467 } 468 469 void flush_icache_user_range(struct vm_area_struct *vma, struct page *page, 470 unsigned long addr, int len) 471 { 472 unsigned long maddr; 473 474 maddr = (unsigned long) kmap(page) + (addr & ~PAGE_MASK); 475 flush_icache_range(maddr, maddr + len); 476 kunmap(page); 477 } 478 EXPORT_SYMBOL(flush_icache_user_range); 479 480 /* 481 * This is called at the end of handling a user page fault, when the 482 * fault has been handled by updating a PTE in the linux page tables. 483 * We use it to preload an HPTE into the hash table corresponding to 484 * the updated linux PTE. 485 * 486 * This must always be called with the pte lock held. 487 */ 488 void update_mmu_cache(struct vm_area_struct *vma, unsigned long address, 489 pte_t pte) 490 { 491 #ifdef CONFIG_PPC_STD_MMU 492 unsigned long access = 0, trap; 493 #endif 494 unsigned long pfn = pte_pfn(pte); 495 496 /* handle i-cache coherency */ 497 if (!cpu_has_feature(CPU_FTR_COHERENT_ICACHE) && 498 !cpu_has_feature(CPU_FTR_NOEXECUTE) && 499 pfn_valid(pfn)) { 500 struct page *page = pfn_to_page(pfn); 501 if (!PageReserved(page) 502 && !test_bit(PG_arch_1, &page->flags)) { 503 if (vma->vm_mm == current->active_mm) { 504 #ifdef CONFIG_8xx 505 /* On 8xx, cache control instructions (particularly 506 * "dcbst" from flush_dcache_icache) fault as write 507 * operation if there is an unpopulated TLB entry 508 * for the address in question. To workaround that, 509 * we invalidate the TLB here, thus avoiding dcbst 510 * misbehaviour. 511 */ 512 _tlbie(address); 513 #endif 514 __flush_dcache_icache((void *) address); 515 } else 516 flush_dcache_icache_page(page); 517 set_bit(PG_arch_1, &page->flags); 518 } 519 } 520 521 #ifdef CONFIG_PPC_STD_MMU 522 /* We only want HPTEs for linux PTEs that have _PAGE_ACCESSED set */ 523 if (!pte_young(pte) || address >= TASK_SIZE) 524 return; 525 526 /* We try to figure out if we are coming from an instruction 527 * access fault and pass that down to __hash_page so we avoid 528 * double-faulting on execution of fresh text. We have to test 529 * for regs NULL since init will get here first thing at boot 530 * 531 * We also avoid filling the hash if not coming from a fault 532 */ 533 if (current->thread.regs == NULL) 534 return; 535 trap = TRAP(current->thread.regs); 536 if (trap == 0x400) 537 access |= _PAGE_EXEC; 538 else if (trap != 0x300) 539 return; 540 hash_preload(vma->vm_mm, address, access, trap); 541 #endif /* CONFIG_PPC_STD_MMU */ 542 } 543